Herring Fish (Clupea harengus) Oil Production and Evaluation for Industrial Uses

It is a well known fact that the lipid (oil) extracted from various fish species can be of industrial benefit if properly extracted and processed. In this study herring fish oil was analyzed using quantitative and qualitative analysis in other to provide an assessment of the quality of the oil for industrial purposes. This work focuses on the production of oil from frozen herring fish (Clupea harengus) as the raw material readily available on the market, by evaluating by the oil using chemical and physical analysis and refining the oil by degumming, neutralizing, drying, and decolorizing. The experimental results revealed that the rate of extraction increases with time until maximum extraction took place using an average size of 780 µm. Every 10.64 g of dried sample used has about 4.34 g of oil extracted for five hours. The extracted herring fish oil contains two essential unsaturated fatty acids, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), which could be of great industrial importance.     

Dry Degumming of Corn-oil for Biodiesel Using a Tubular Ceramic Membrane

Gum removal from vegetable oils applied for diesel fuel is an essential process, since the presence of gum in direct use to the diesel engine might cause plugging in the engine filters, lines and injectors. In the biodiesel production, the use of crude vegetable oils without degumming might decrease conversion rate and hard to separate glycerol from biodiesel, during and after trans-esterification reaction respectively. Ultrafiltration is potential technology for degumming of crude vegetable oils, however since the oil constituents have nearly close molecular weight, the membrane degumming process is a difficult process. In order to understand the membrane degumming process in corn-oil, both experimental and computational works have been conducted. Dry degumming process of corn-oil has been carried out using a tubular ceramic membrane, and the effects of process conditions (temperature, trans-membrane pressure, cross flow velocity) and concentration polarization were investigated. Computational fluid dynamics simulation based on Galerkin finite element methods (FEM) has been carried out and used to predict the retention layer occurred during inside-out operation of membrane degumming. The numerical results show that the increasing of crossflow velocity lead to increase axial Reynolds number, and on the other hand decrease the thickness of the retention layer. In the x/R=1.0 position, the retention layer thicknesses were δp= 4.0x10^-4 m and δp= 1.7x10^-4 m, for Re=1000 and Re=10000, respectively. Moreover, the effect of increasing Schmidt number gives a significant retention layer thickness decline, i.e. from δp= 4.8x10^-4 m to δp= 2.2x10^-4 m, by using Sc=4x10⁵ to Sc=1.3x10⁶, respectively. The Schmidt numbers depends on the diffusion behavior of solute in the solvent, and has been concluded that wet-degumming process was a better method to prevent higher concentration polarization close to the membrane wall.     

柴油溶剂中脂肪酶催化高酸值废油脂酯化制备生物柴油

采用0＃柴油作为反应溶剂,利用固定化脂肪酶催化高酸值废油脂与甲醇酯化反应制备生物柴油。来源于Candida antarctica的固定化脂肪酶Novozym435在0＃柴油溶剂中具有极高的催化活性。以酸价高达157×10-3的废油脂为原料,废油脂质量比10%的Novozym435,甲醇与废油脂初始摩尔比2∶1,0＃柴油与废油脂质量比5∶1,摇床摇速170r/min,50℃下反应2h甲酯化率可达95.10%。0＃柴油作为反应溶剂有效地溶解了高酸值废油脂和甲醇,降低了反应体系的黏度和消除了甲醇对Novozym435的负面影响,提高了Novozym435的稳定性。同时,0＃柴油溶剂对未脱胶废油脂中残留的对脂肪酶有害的磷脂等胶类物质具有一定的稀释作用。该工艺省却了溶剂蒸馏的繁琐工序,直接得到脂肪酸甲酯和石化柴油的混合燃料。     

Bench-scale membrane degumming of crude vegetable oil: Process optimization

Crude vegetable oils contain various minor substances such as phospholipids, coloring pigments, and free fatty acids (FFA) that may affect the quality of the finished oil. Reduction of energy costs and waste disposal are major concerns for many oil refiners who are looking for alternative methods to improve conventional refining methods, and during the last decade, energy-efficient membrane separation technology has evolved dramatically. This paper reports the cross-flow bench-scale crude vegetable oil membrane degumming test results using newly available, modified, hexane-resistant, high flux, and high selectivity non-aqueous membranes. Two membranes (DS-7 and AN03) were evaluated for their flux and rejection properties. Process parameters including pressure, temperature, feed velocity and volumetric concentration factor were examined. A 99.6% rejection of phospholipids and a flux of 26.8 l/m² h were achieved at pressure 300 psi, temperature 40°C, and feed velocity 220 l/h using DS-7 membrane, and significant reduction of coloring pigments was observed as well. Membrane fouling presented no big problem.     

Application of Low-Pressure Plasma Pretreatment in Silk Fabric Degumming Process

A novel and effective method was developed for raw silk fabric degumming with the application of low-pressure argon plasma in pretreatment combining a subsequent one-step mild wet-chemical process. The plasma parameters, such as argon pressure, discharge power and exposure time, were optimized according to degumming loss and the properties of fabric such as capillary rise, tensile strength, bending rigidity, etc. An optimized plasma pretreatment for raw silk fabric degumming was at 80 Pa of argon gas and 60 W glow discharge power for 5–10 min. The raw silk fabric and fibers pretreated by argon plasma were characterized by scanning electronic microscopy and X-ray powder diffraction. In comparison with a conventional degumming process, the proposed method achieved comparable degumming efficiency and properties of silk fabric, and it was more environmentally friendly by shortening the conventional wet-chemical treatment process, saving the dosage of degumming agents, water and energy.     

Lignin peroxidase production by Streptomyces viridosporus T7A

Lignin peroxidase (LiP) production cost should be reduced to justify its use in the control of environmental pollution. In this work, we studied the enzyme production by Streptomyces viridosporus T7A using glucose or corn oil as a carbon source having 0.65% yeast extract as a nitrogen source. Enzyme activity, observed using either 0.65% glucose or corn oil at 0.1, 0.5, and 1.0% concentration, was 300, 150, 300, and 200 U/L, respectively. Although higher enzyme activity was obtained in both media containing 0.65% glucose and 0.5% corn oil, the use of corn oil resulted in a better LiP stability. When combined carbon sources were used, higher values of enzyme activity (360, 350, and 225 U/L) were observed in media with 0.65% glucose and supplemented with 0.1, 0.5, and 1.0% corn oil, respectively. Although the presence of both glucose and 0.5% corn oil is favorable for LiP production, satisfactory results in terms of enzyme production and stability could be also observed using 0.5% corn oil as a sole carbon source, which may lead to reduced production costs of the LiP enzyme.     

蚕丝中蛋白构象含量与其力学性质间的关系

丝蛋白 (Ｆｉｂｒｏｉｎ)是一种具有优异力学性能的天然有机高分子材料 ,蚕丝是最具代表性的一种 .它既有较高的强度 ,又有较强的韧性 ,其强度甚至超过钢丝 .但蚕丝具有如此优异力学性能的机理还不很清楚[1～ 3 ] .通常认为在丝蛋白中有 3种二级结构 (构象 ) ,即α 螺旋 (α ｈｅｌｉｘ) ,β 片层 ( β ｓｈｅｅｔ)和无规线团 (Ｒａｎｄｏｍｃｏｉｌ) [4,5] .α 螺旋是由链内氢键引起的蛋白结构 ,而 β 片层是由链间氢键引起的蛋白结构 .但有研究表明[3 ,6] ,丝蛋白中还存在另一种由 4个氨基酸残基组成的发夹式结构 :β 转角 ( β ｔｕｒｎ)…     

Comparative study on enhanced pectinase and alkali-oxygen degummings of sisal fibers

This paper reports an improved traditional fiber degumming method, where sisal fibers were treated by alkali oxygen and pectinase, respectively, after the solute alkali pretreatment. To explore the influence of various factors on its degumming, efficiency of degumming through single factor and orthogonal experiments was aasessed. The results showed that pectinase/alkali-oxygen method after the first alkali treatment had a good effect on the degumming of sisal fiber, and most of the non-cellulose components such as hemicellulose, lignin and pectin had been removed. After pectinase treatment, the cellulose content and crystallinity were 71.87% and 66.29%, respectively. After alkaline oxygen treatment, the cellulose content was 77.16%, and the crystallinity was 69.09%. In terms of degumming rate, alkali oxygen treatment worked better than pectinase treatment, the degumming rate of pectinase method was about 10%, while that of alkali-oxygen method was more than 20%. In other hand, the pectinase method was much milder and had less damage to fibers. It would provide some references for the future application and development of sisal fiber.

     

Kinetic Modeling of Solvent-Free Lipase-Catalyzed Partial Hydrolysis of Palm Oil

This work reports the experimental data and kinetic modeling of diacylglycerol (DAG) production from palm oil using a commercial immobilized lipase (Lipozyme RM IM) in a solvent-free medium. The experiments were performed in batch mode, at 55?°C and 400?rpm, and the effects of enzyme concentration (0.68?C2.04?wt% related to the mass of substrates), initial water concentration (5?C15?wt% related to the mass of oil), and reaction time were evaluated. A novel kinetic model is presented based on the ordered-sequential bi?Cbi mechanism considering hydrolysis and esterification steps, in which a correlation between water-in-oil solubility and surfactant molecules concentration in the oil allowed the model to describe the induction period in the beginning of the hydrolysis reaction. Moreover, mass transfer limitations related to the enzyme concentration in the system were also taken into account. The proposed model presented a very satisfactory agreement with the experimental data, thus allowing a better understanding of the reaction kinetics. The best conditions obtained for the product (partially hydrolyzed palm oil) in terms of DAG yield (35.91?wt%) were 2.87?wt% enzyme/substrate, 2.10?wt% water/oil, and 72?h of reaction.     

Continuous fabrication of biocatalyst immobilized microparticles using photopolymerization and immiscible liquids in microfluidic systems

We report a novel technique for manufacturing polymeric microparticles containing biocatalysts by the behavior of immiscible liquids in microfluidic systems and in situ photopolymerization. The approach utilizes a UV-polymerizable hydrogel/enzyme solution and an immiscible oil solution. The oil and hydrogel solutions form emulsions in pressure-driven flow in microchannels at high values of the dimensionless capillary number (Ca). The resultant hydrogel droplets are then polymerized in situ via exposure to 365 nm UV light. This technique allows for the generation of monodisperse particles whose size can be controlled by the regulation of flow rates. In addition, both manufacturing microparticles and immobilizing biocatalysts can be performed simultaneously and continuously.     

A study on the effects of ozone treatment on the properties of raw and degummed mulberry silk fabrics

Ozone is a powerful oxidizing agent and is widely used in various applications, which includes bleaching of cotton. Its application on the processing of silk is non-existent. Research studies on degumming and bleaching of silk reveal that almost no work involving ozone has been carried out. Therefore a study was carried out to understand the effects of process parameters namely wet pickup, pH and time in the ozone treatment of raw and degummed mulberry and tassar silk fabrics on their properties. This paper reports on the effects of ozone treatment on the mulberry silk fabrics. The study was extended with a view to compare the ozone treatment with soap degumming and hydrogen peroxide treatment carried out on raw and degummed mulberry silk fabrics, respectively. The treatment results in increase in yellowness index and amino group content and decrease in breaking strength and elongation, weight and flexural rigidity. The results obtained are substantiated with tyrosine content, scanning electron micrographs and infrared spectroscopy of the treated materials. The effect of pH on the treatment is maximum up to pH 4 and then decreases. The treatment is more severe when the wet pickup used is 50% compared to that of 10 and 100%. With respect to treatment time, though the severity increases with time, it is maximum during the first 10 min of the treatment. Soap degumming of raw silk fabric results in lower yellowness index and flexural rigidity and lesser loss in breaking strength and elongation compared to that of ozone treated material. There is not much of difference between ozone and hydrogen peroxide treatments of degummed silk fabric except for the lower yellowness index obtained in the latter case.     

Immobilization of Eversa® Transform via CLEA Technology Converts It in a Suitable Biocatalyst for Biolubricant Production Using Waste Cooking Oil

The performance of the previously optimized magnetic cross-linked enzyme aggregate of Eversa (Eversa-mCLEA) in the enzymatic synthesis of biolubricants by transesterification of waste cooking oil (WCO) with different alcohols has been evaluated. Eversa-mCLEA showed good activities using these alcohols, reaching a transesterification activity with isoamyl alcohol around 10-fold higher than with methanol. Yields of isoamyl fatty acid ester synthesis were similar using WCO or refined oil, confirming that this biocatalyst could be utilized to transform this residue into a valuable product. The effects of WCO/isoamyl alcohol molar ratio and enzyme load on the synthesis of biolubricant were also investigated. A maximum yield of around 90 wt.% was reached after 72 h of reaction using an enzyme load of 12 esterification units/g oil and a WCO/alcohol molar ratio of 1:6 in a solvent-free system. At the same conditions, the liquid Eversa yielded a maximum ester yield of only 34%. This study demonstrated the great changes in the enzyme properties that can be derived from a proper immobilization system. Moreover, it also shows the potential of WCO as a feedstock for the production of isoamyl fatty acid esters, which are potential candidates as biolubricants.     

Extraction of Oil from Flaxseed (<Emphasis Type="Italic">Linum usitatissimum</Emphasis> L.) Using Enzyme-Assisted Three-Phase Partitioning

In this study, enzyme-assisted three-phase partitioning (EATPP) was used to extract oil from flaxseed. The whole procedure is composed of two parts: the enzymolysis procedure in which the flaxseed was hydrolyzed using an enzyme solution (the influencing parameters such as the type and concentration of enzyme, temperature, and pH were optimized) and three-phase partitioning (TPP), which was conducted by adding salt and t-butanol to the crude flaxseed slurry, resulting in the extraction of flaxseed oil into alcohol-rich upper phase. The concentration of t-butanol, concentration of salt, and the temperature were optimized to maximize the extraction yield. Under optimized conditions of a 49.29 % t-butanol concentration, 30.43 % ammonium sulfate concentration, and 35 °C extraction temperature, a maximum extraction yield of 71.68 % was obtained. This simple and effective EATPP can be used to achieve high extraction yields and oil quality, and thus, it is potential for large-scale oil production.     

Sustainable process for the pretreatment and dyeing of Eri silk

The green process route for pre-treatment and dyeing of Eri silk is proposed and investigated in this study. The natural plant-based saponins were extracted from Sapindus mukorossi by aaqueous extraction technique. Extracted Saponins showed a high emulsification index (68), low surface tension (41 dyne/cm), mild foaming (200 mm), and a slightly acidic pH, these characteristic properties are considered to be best suited for the processing of silk. The degumming was performed using Sapindus extract liquid with a concentration of 10% (owf) for 60 min at a temperature of 95 °C. The Eri silk degumming produced similar weight loss (4.63%), water absorbency (3 s) and optical properties - whiteness (80.33), yellowness (2.27) and brightness (70.05), as compared to the conventional process. The tensile strength (8.28 kgf)) and elongation (34.29%) was found to be better than the properties of the fabric processed with conventional chemical processing. The dyeing of degummed and bleached Eri silk with natural dyes showed comparable colour depth and uniformity of shade as compared to the conventional chemical processing. The overall fastness performance of dyed Eri silk was in line with the industry standards. Advanced characterization techniques such as FTIR was used for structural analysis of treated Eri silk.     

ETUDE PAR FLUORESCENCE DE BASES DE SCHIFF DU PYRIDOXAL, COMPARAISON AVEC LA L ASPARTATE-AMINOTRANSFERASE

Abstract— –Absorption and emission spectra of Schiff bases of pyridoxal-HCI or pyridoxal-5-phosphate with L-valine, n -butylamine or N-α-acetyl-L-lysine-N-methylamide have been studied as a function of pH. We can write the complete ionization diagram and equilibria. The results of Martell[6] are confirmed: the forms analogous to the coenzyme in aspartate aminotransferase, which absorb at 410 nm and 360 nm (or 340 nm for the Schiff base with n-butyl-amine) have the phenol OH ionized; the imine nitrogen is protonated for species absorbing at 410nm (in the enzyme: inactive form and complex with aminoacid) and unprotonated for species absorbing at 360 nm (in the enzyme, active form). Their fluorescence wavelengths are respectively 500 nm and 430 nm. Protonation of the pyridine nitrogen of these forms does not shift the absorption band; the fluorescence intensity is 20-fold greater for the N-protonated forms.
The real pK of the imine nitrogen is 8.5 ±0.8 for species with pyridine N-protonated or 10.4 for the non-protonated forms. The observed pK 6.3 in the enzyme can be explained if the imine nitrogen is hydrogen bonded to an amino-acid side chain of the protein: lysine, tyrosine, serine, sulfhydryl.
The quantum yield of the coenzyme fluorescence in the enzyme has been compared to that of the analogous Schiff base (absorbing at the same wavelength). According to the results, we cannot deduce whether the pyridine nitrogen is protonated in pyridoxal form of the enzyme.
If it is protonated, as in the pyridoxamine form, the coenzyme environment is not the same in the two forms. If the pyridine nitrogen is unprotonated in the pyridoxal form and protonated in the pyridoxamine form, the environment of the coenzyme is the same in these two forms of the enzyme.     

Fatty and resin acid analysis in tall oil products via supercritical fluid extraction-supercritical fluid reaction using enzymatic catalysis

Supercritical fluid extraction (SFE) is combined with supercritical fluid reaction (SFR) in an analytical mode to assess tall oil products for their fatty or resin acid content or both. The SFR consists of an inline enzymatically catalyzed reaction in which a lipase transesterifies specific lipids with methanol. The SFE-SFR sequence is conducted employing commercially available extractors using supported lipases in the extraction cell to form methyl esters. In this study, six different commercially available lipases are screened for activity. The SFE-SFR extracts are analyzed by capillary gas chromatography and supercritical fluid chromatography and then compared with tall oil products derivatized by conventional chemical derivatization techniques.     

Determination of the fatty-acid composition of soybean oil by high-pressure liquid chromatography

A method for determining the fatty-acid composition of soybean oil by using high-pressure liquid chromatography (HPLC) is discussed and compared with the determination using gas chromatography. The oil is saponified and an aliquot is treated directly to form the p-bromophenacyl esters of the fatty acids, which are separated by gradient-elution HPLC. It is shown that glycerol does not interfere with the esterification, thus obviating the solvent extraction previously used to isolate fatty acids from biological samples.     

Metal nanoparticle formation in oil media using di(2-ethylhexyl) phosphoric acid (HDEHP)

The metal ion extractant (HDEHP) that is commonly employed in liquid membrane extraction has been shown to stabilise Ag and Cu nanoparticles in oil media of size 5 and 10 nm, respectively. The particle are formed by reduction of the metal salts of HDEHP that are oil soluble and shown by SANS to form small reversed micelles of radius approximately 1 nm. The extractant is also effective at stabilising particles of similar size in an oil phase when the metal ion (e.g., AgNO3) is reduced in a coexisting aqueous phase.     

Bond interchange reactions in functionalized triglyceride oil/poly(ethylene terephthalate) compositions

Naturally functionalized triglyceride oils are renewable resources which contain reactive chemical groups, hydroxyl in the case of castor oil, and epoxide in the case of vernonia oil. In this article, the reaction of these groups, and the ester linkages between the glycerol and acid residue portions of the oil molecule with poly(ethylene terephthalate) (PET) is investigated through a variety of means. Multiple reactions are possible in the triglyceride–PET system, some of which form a copolymer that increases miscibility, and if allowed to continue, forms a completely random copolymer mixture. Among the numerous reactions possible, PET–ester exchange with the hydroxyl or epoxide functionality of the triglyceride oils is found to be the most significant, and the effects of these and other reactions are observed and structural implications discussed. © 1993 John Wiley & Sons, Inc.     

De novo design of synthetic di-iron(I) complexes as structural models of the reduced form of iron-iron hydrogenase

Simple synthetic di-iron dithiolate complexes provide good models of the composition of the active site of the iron-iron hydrogenase enzymes. However, the formally Fe(I)Fe(I) complexes synthesized to date fail to reproduce the precise orientation of the diatomic ligands about the iron centers that is observed in the molecular structure of the reduced form of the enzyme active site. This structural difference is often used to explain the fact that the synthetic di-iron complexes are generally poor catalysts when compared to the enzyme. Herein, density functional theory computations are used for the rational design of synthetic complexes as structural models of the reduced form of the enzyme active site. These computations suggest several possible synthetic targets. The synthesis of complexes containing five-atom S-to-S linkers of the form S(CH2)2X(CH2)2S (X = CH2, NH, or O) or pendant functionalities attached to the three-carbon framework is one method. Another approach is the synthesis of asymmetrically substituted complexes, in which one iron center has strongly electron donating ligands and the adjacent iron center has strongly electron accepting ligands. The combination of a sterically demanding S-to-S linker and asymmetric substitution of the CO ligands is predicted to be a particularly effective synthetic target.